Previously it has been known to use cooling nozzles in internal combustion engines to direct a spray of oil to the underside of the pistons for the purpose of cooling and/or lubrication. Typically such nozzles are mounted to the cylinder block and have some means for communicating with the oil gallery of the engine. One known type of cooling nozzle is a cartridge style arrangement that is inserted in a through-bore from outside the cylinder block. The through-bore intersects the oil gallery and an orifice on the cartridge communicates oil from the gallery to the nozzle. This arrangement requires o-rings to prevent oil leakage. Also the length to diameter ratio of the nozzle is limited due to the requirements for mounting the nozzle via the through-bore. Another type of nozzle mounting arrangement is disclosed in U.S. Pat. No. 6,298,810 to Chimonides et al. This nozzle consists of an annular mounting collar having a cylindrical outer surface and a tube projecting generally radially from the mounting collar. The engine block is formed with a drilled and tapped screw threaded bore that is drilled into the surface of the engine block to intersect the oil gallery. A special capscrew is inserted through the collar into the threaded bore to retain the collar to the cylinder block. The capscrew has special machining to allow oil to flow from the oil gallery to the nozzle. A locating pin is provided to maintain the radial position of the nozzle.
New piston configurations such as the monobloc design disclosed in U.S. Pat. No. 6,526,871 to Zhu et al. require cooling and lubrication in the under-crown area, however such monobloc designs have cooling galleries that are typically accessible only through one or two holes in the under-crown of the piston. Because it is necessary to direct a flow of oil to these access holes, existing nozzle designs cannot be used.
Accordingly, there is a clear need in the art for a cooling nozzle mounting arrangement which allows for internal centrally located mounting, has a longer nozzle, and provides intermittent flow without the need for special screws and/or o-rings.